| 摘要 |
PROBLEM TO BE SOLVED: To provide a down-sized light quantity controller where outside diameter and space in an optical axis direction are made small and in which plural blades such as a light quantity diaphragm blade and a shutter blade and their driving devices for them are assembled in the periphery of the optical axis of a photographing lens part. SOLUTION: Blade members 3 and 5 are arranged at a first base plate 1 having an optical axis aperture 8, so as to face to the optical axis aperture 8, and a nearly cylindrical coil 68 and a magnet rotor 65 are arranged in parallel by leaving a space on the base plate, so that an axial direction is directed in the optical axis direction. Then, a pair of magnetic induction members 66 and 67 are extended from both end parts of the coil 68 in the optical axis direction, and top end parts 66b and 67b are arranged so as to be counterposed by sandwiching the magnet rotor 65. A light quantity controller is provided with regulating means 74 and 75 to regulate motion, with which the rotation of the magnet rotor 68 to obtain rotational force by the magnetic action of the magnet rotor 68 with two NS magnetic poles is oscillated by a specified angle between two magnetic poles formed by the magnetic induction members 66 and 67, by generating two magnetic poles mutually opposed in terms of NS by the pair of the magnetic induction members 66 and 67.
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